Series "F" coaxial 75 Ohm connectors are widely used for domestic TV and ancillarty equipments. They are a low-cost low mating-life connector where the centre-pin may be the inner conductor of the coaxial cable and deemed suitable for use at frequencies up to 1GHz.
The coupling thread is 3/8" x 32tpi UNEF
Adaptors to other coaxial connectrs are often deployed where better mating life is required or connection to larger lower-loss feeder cables is needed.
Weather-proofed plugs (with an internal gasket) are available, however, after mating a wrapping of self-amalgamating tape is highly desirable so as to ensure the water-tight integruity.
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